Dual antennas or single?

I fully agree also. And I have spent a lot of time and money trying single and dual antennas, and I always end up with duals. Trailer signal loss & and corners facing away from antenna made noticeable differences when talking to other drivers with single antennas and hearing their signal fading in & out, and by also using a signal antenna with the same results. I have been using dual antennas again and I don't loose side to side distances. I was talking skip facing west and talking to Canada. So I still say with a tall trailer dual. But on my car I run a single trunk lip mounted wilson 1000 made into a W-5000 by exchanging the coil from a roof mount w-5000, for better a ground & ground plane on a old school metal car.

 

Always and still today run single antenna, less coax, less connections, less problems and i believe easier to tune.

Had all kinds of antenna predators, star gun, monkey, francis, skipshooters....i have sold everything that i had and should get my new sirio mag mount this week.

My truck has antennas on both side i use one for the radio and the other i use as a tv antenna.

 

2 elements reshapes the radiation pattern to a more symmetrical pattern and helps cancel out receive to the sides which increases reception front to rear.
similar concept to using a multiple element beam.

 

2 elements is more complicated to troubleshoot, but is slightly more efficient front to rear.

 

The best spot for a single antenna is in the middle of my roof. Good luck doing that on a big truck unless you have a flat top Peterbilt. The further you get from the center of the roof the more lopsided the radiation pattern will be but unfortunately anything you do on a commercial truck is always going to be a compromise. I run a single antenna in the middle of my roof on my Chevy Tahoe and it works about as well as a base station but you will never accomplish the same results on a tractor trailer unless you bolt a base antenna to the catwalk. If I'm in a truck for a long time I always run two antennas simply for the cancellation of signals incoming from the sides and extra gain front-to-rear.

 

Old post but that simply isnt so.
CB radios use a linear path to transmit and recieve signals. When pulling a trsiler such as a dry van or reefer your trailer can and will partially block transmissions. For instance if your pulling a trailer and your antenna is mounted on the passenger mirror then your radio signal will be partially blocked on your driver side rear. Having dual phase coax and antennas corrects this issue.
Two antennas do not however increase modulation or output. Note that its important that they be at least 5' apart or else the user will have a decrease in performance.
Another way to reduce interference is to have an antenna that is long enough to sit higher yhan the top of your vehicle.
But nonetheless a well tuned, propperly installed and grounded radio and one single antenna mounted in an ideal location will give the user peak performance. After all truckers need only a mile or two ahead and across the median or across the lot to the scale house .